But even knowing that, some patients have a hard time hitting the gym. According to the Centers for Disease Control and Prevention, only 21 percent of adults are doing enough aerobic and muscle-strengthening activities.

In an attempt to get at-risk patients moving, researchers at the Perelman School of Medicine at the University of Pennsylvania rounded up 105 people with ischemic heart disease, a condition where coronary arteries restrict blood supply to the heart.

All participants received wrist-worn fitness tracking devices, such as Fitbits or Apple Watches. A smaller group was also assigned a daily step- count goal, plus monetary motivation: an account with $14 deposited every week — and $2 subtracted for every day they fell short of their goals.

Patients in that “incentive” group “significantly increased physical activity levels during the six-month [study] period,” logging 1,368 more steps per day than the fitness-trackers-only group, lead study author and cardiologist Dr. Neel Chokshi says in a press release.

Plus, the payoff lasted longer than the payday. Money-motivated participants continued to outstep their fellow study participants, even after the study authors stopped funding (and subtracting from) the accounts.